# Part of Odoo. See LICENSE file for full copyright and licensing details.
import contextlib
import re
from lxml import etree
from unittest.mock import Mock, MagicMock, patch

from werkzeug.exceptions import NotFound
from werkzeug.test import EnvironBuilder

import odoo
from odoo.tests.common import HttpCase, HOST
from odoo.tools.misc import DotDict, frozendict


@contextlib.contextmanager
def MockRequest(
        env, *, path='/mockrequest', routing=True, multilang=True,
        context=frozendict(), cookies=frozendict(), country_code=None,
        website=None, remote_addr=HOST, environ_base=None,
        # website_sale
        sale_order_id=None, website_sale_current_pl=None,
):

    lang_code = context.get('lang', env.context.get('lang', 'en_US'))
    env = env(context=dict(context, lang=lang_code))
    request = Mock(
        # request
        httprequest=Mock(
            host='localhost',
            path=path,
            app=odoo.http.root,
            environ=dict(
                EnvironBuilder(
                    path=path,
                    base_url=HttpCase.base_url(),
                    environ_base=environ_base,
                ).get_environ(),
                REMOTE_ADDR=remote_addr,
            ),
            cookies=cookies,
            referrer='',
            remote_addr=remote_addr,
        ),
        type='http',
        future_response=odoo.http.FutureResponse(),
        params={},
        redirect=env['ir.http']._redirect,
        session=DotDict(
            odoo.http.get_default_session(),
            geoip={'country_code': country_code},
            sale_order_id=sale_order_id,
            website_sale_current_pl=website_sale_current_pl,
        ),
        geoip={},
        db=None,
        env=env,
        registry=env.registry,
        cr=env.cr,
        uid=env.uid,
        context=env.context,
        lang=env['res.lang']._lang_get(lang_code),
        website=website,
    )
    if website:
        request.website_routing = website.id

    # The following code mocks match() to return a fake rule with a fake
    # 'routing' attribute (routing=True) or to raise a NotFound
    # exception (routing=False).
    #
    #   router = odoo.http.root.get_db_router()
    #   rule, args = router.bind(...).match(path)
    #   # arg routing is True => rule.endpoint.routing == {...}
    #   # arg routing is False => NotFound exception
    router = MagicMock()
    match = router.return_value.bind.return_value.match
    if routing:
        match.return_value[0].routing = {
            'type': 'http',
            'website': True,
            'multilang': multilang
        }
    else:
        match.side_effect = NotFound

    def update_context(**overrides):
        request.context = dict(request.context, **overrides)

    request.update_context = update_context

    with contextlib.ExitStack() as s:
        odoo.http._request_stack.push(request)
        s.callback(odoo.http._request_stack.pop)
        s.enter_context(patch('odoo.http.root.get_db_router', router))

        yield request

# Fuzzy matching tools

def distance(s1="", s2="", limit=4):
    """
    Limited Levenshtein-ish distance (inspired from Apache text common)
    Note: this does not return quick results for simple cases (empty string, equal strings)
        those checks should be done outside loops that use this function.

    :param s1: first string
    :param s2: second string
    :param limit: maximum distance to take into account, return -1 if exceeded

    :return: number of character changes needed to transform s1 into s2 or -1 if this exceeds the limit
    """
    BIG = 100000  # never reached integer
    if len(s1) > len(s2):
        s1, s2 = s2, s1
    l1 = len(s1)
    l2 = len(s2)
    if l2 - l1 > limit:
        return -1
    boundary = min(l1, limit) + 1
    p = [i if i < boundary else BIG for i in range(0, l1 + 1)]
    d = [BIG for _ in range(0, l1 + 1)]
    for j in range(1, l2 + 1):
        j2 = s2[j - 1]
        d[0] = j
        range_min = max(1, j - limit)
        range_max = min(l1, j + limit)
        if range_min > 1:
            d[range_min - 1] = BIG
        for i in range(range_min, range_max + 1):
            if s1[i - 1] == j2:
                d[i] = p[i - 1]
            else:
                d[i] = 1 + min(d[i - 1], p[i], p[i - 1])
        p, d = d, p
    return p[l1] if p[l1] <= limit else -1

def similarity_score(s1, s2):
    """
    Computes a score that describes how much two strings are matching.

    :param s1: first string
    :param s2: second string

    :return: float score, the higher the more similar
        pairs returning non-positive scores should be considered non similar
    """
    dist = distance(s1, s2)
    if dist == -1:
        return -1
    set1 = set(s1)
    score = len(set1.intersection(s2)) / len(set1)
    score -= dist / len(s1)
    score -= len(set1.symmetric_difference(s2)) / (len(s1) + len(s2))
    return score

def text_from_html(html_fragment, collapse_whitespace=False):
    """
    Returns the plain non-tag text from an html

    :param html_fragment: document from which text must be extracted

    :return: text extracted from the html
    """
    # lxml requires one single root element
    tree = etree.fromstring('<p>%s</p>' % html_fragment, etree.XMLParser(recover=True))
    content = ' '.join(tree.itertext())
    if collapse_whitespace:
        content = re.sub('\\s+', ' ', content).strip()
    return content